Modern manufacturing technology allows many items to be produced on-demand. For example, many items can be produced quickly using three-dimensional printers to build the items layer by layer under computer control. However, in many cases, a user must manually sand, paint, and/or perform other additional processing on a resulting item before the item is ready for final use. Such post-processing may be time-consuming and/or difficult to consistently perform on multiple copies of the item, leading to increased costs and/or user frustration.